package org.soarsky.wealthchengdu.view;

import org.soarsky.wealthchengdu.R;
import org.soarsky.wealthchengdu.appliction.MyAppliction;
import org.soarsky.wealthchengdu.util.Config;

import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.LinearInterpolator;
import android.view.animation.RotateAnimation;
import android.widget.AdapterView;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ProgressBar;
import android.widget.ScrollView;
import android.widget.TextView;


public class PullToRefreshView extends LinearLayout {
    private static final String TAG = "PullToRefreshView";
    // refresh states
    private static final int PULL_TO_REFRESH = 2;
    private static final int RELEASE_TO_REFRESH = 3;
    private static final int REFRESHING = 4;
    // pull state
    private static final int PULL_UP_STATE = 0;
    private static final int PULL_DOWN_STATE = 1;
    /**
     * last y
     */
    private int mLastMotionY;
    /**
     * lock
     */
    private boolean mLock;
    /**
     * header view
     */
    private View mHeaderView;
    /**
     * footer view
     */
    private View mFooterView;
    /**
     * list or grid
     */
    private AdapterView<?> mAdapterView;
    /**
     * scrollview
     */
    private ScrollView mScrollView;
    /**
     * header view height
     */
    private int mHeaderViewHeight;
    /**
     * footer view height
     */
    private int mFooterViewHeight;
    /**
     * header view image
     */
    private ImageView mHeaderImageView;
    /**
     * footer view image
     */
    private ImageView mFooterImageView;
    /**
     * header tip text
     */
    private TextView mHeaderTextView;
    /**
     * footer tip text
     */
    private TextView mFooterTextView;
    /**
     * header refresh time
     */
    private TextView mHeaderUpdateTextView;
    /**
     * footer refresh time
     */
    // private TextView mFooterUpdateTextView;
    /**
     * header progress bar
     */
    private ProgressBar mHeaderProgressBar;
    /**
     * footer progress bar
     */
    private ProgressBar mFooterProgressBar;
    /**
     * layout inflater
     */
    private LayoutInflater mInflater;
    /**
     * header view current state
     */
    private int mHeaderState;
    /**
     * footer view current state
     */
    private int mFooterState;
    /**
     * pull state,pull up or pull down;PULL_UP_STATE or PULL_DOWN_STATE
     */
    private int mPullState;
    /**
     * 变为向下的箭头,改变箭头方向
     */
    private RotateAnimation mFlipAnimation;
    /**
     * 变为逆向的箭头,旋转
     */
    private RotateAnimation mReverseFlipAnimation;
    /**
     * footer refresh listener
     */
    private OnFooterRefreshListener mOnFooterRefreshListener;
    /**
     * footer refresh listener
     */
    private OnHeaderRefreshListener mOnHeaderRefreshListener;
    /**
     * last update time
     */
    private String mLastUpdateTime;

    public PullToRefreshView(Context context, AttributeSet attrs) {
	super(context, attrs);
	init();
    }

    public PullToRefreshView(Context context) {
	super(context);
	init();
    }

    /**
     * init
     * 
     * @description
     * @param context
     */
    private void init() {
	// Load all of the animations we need in code rather than through XML
	mFlipAnimation = new RotateAnimation(0, -180,
		RotateAnimation.RELATIVE_TO_SELF, 0.5f,
		RotateAnimation.RELATIVE_TO_SELF, 0.5f);
	mFlipAnimation.setInterpolator(new LinearInterpolator());
	mFlipAnimation.setDuration(250);
	mFlipAnimation.setFillAfter(true);
	mReverseFlipAnimation = new RotateAnimation(-180, 0,
		RotateAnimation.RELATIVE_TO_SELF, 0.5f,
		RotateAnimation.RELATIVE_TO_SELF, 0.5f);
	mReverseFlipAnimation.setInterpolator(new LinearInterpolator());
	mReverseFlipAnimation.setDuration(250);
	mReverseFlipAnimation.setFillAfter(true);

	mInflater = LayoutInflater.from(getContext());
	// header view 在此添加,保证是第一个添加到linearlayout的最上端
	addHeaderView();
    }

    private void addHeaderView() {
	// header view
	mHeaderView = mInflater.inflate(R.layout.refresh_header, this, false);

	mHeaderImageView = (ImageView) mHeaderView
		.findViewById(R.id.pull_to_refresh_image);
	mHeaderTextView = (TextView) mHeaderView
		.findViewById(R.id.pull_to_refresh_text);
	mHeaderUpdateTextView = (TextView) mHeaderView
		.findViewById(R.id.pull_to_refresh_updated_at);
	mHeaderProgressBar = (ProgressBar) mHeaderView
		.findViewById(R.id.pull_to_refresh_progress);
	// header layout
	measureView(mHeaderView);
	mHeaderViewHeight = mHeaderView.getMeasuredHeight();
	LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT,
		mHeaderViewHeight);
	// 设置topMargin的值为负的header View高度,即将其隐藏在最上方
	params.topMargin = -(mHeaderViewHeight);
	// mHeaderView.setLayoutParams(params1);
	addView(mHeaderView, params);

    }

    private void addFooterView() {
	// footer view
	mFooterView = mInflater.inflate(R.layout.refresh_footer, this, false);
	mFooterImageView = (ImageView) mFooterView
		.findViewById(R.id.pull_to_load_image);
	mFooterTextView = (TextView) mFooterView
		.findViewById(R.id.pull_to_load_text);
	mFooterProgressBar = (ProgressBar) mFooterView
		.findViewById(R.id.pull_to_load_progress);
	// footer layout
	measureView(mFooterView);
	mFooterViewHeight = mFooterView.getMeasuredHeight();
	LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT,
		mFooterViewHeight);
	// int top = getHeight();
	// params.topMargin =getHeight();
	// 在这里getHeight()==0,但在onInterceptTouchEvent()方法里getHeight()已经有值了,不再是0;
	// getHeight()什么时候会赋值,稍候再研究一下
	// 由于是线性布局可以直接添加,只要AdapterView的高度是MATCH_PARENT,那么footer view就会被添加到最后,并隐藏
	addView(mFooterView, params);
    }

    @Override
    protected void onFinishInflate() {
	super.onFinishInflate();
	// footer view 在此添加保证添加到linearlayout中的最后
	addFooterView();
	initContentAdapterView();
    }

    /**
     * init AdapterView like ListView,GridView and so on;or init ScrollView
     */
    private void initContentAdapterView() {
	int count = getChildCount();
	if (count < 3) {
	    throw new IllegalArgumentException(
		    "this layout must contain 3 child views,and AdapterView or ScrollView must in the second position!");
	}
	View view = null;
	for (int i = 0; i < count - 1; ++i) {
	    view = getChildAt(i);
	    if (view instanceof AdapterView<?>) {
		mAdapterView = (AdapterView<?>) view;
	    }
	    if (view instanceof ScrollView) {
		// finish later
		mScrollView = (ScrollView) view;
	    }
	}
	if (mAdapterView == null && mScrollView == null) {
	    throw new IllegalArgumentException(
		    "must contain a AdapterView or ScrollView in this layout!");
	}
    }

    private void measureView(View child) {
	ViewGroup.LayoutParams p = child.getLayoutParams();
	if (p == null) {
	    p = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT,
		    ViewGroup.LayoutParams.WRAP_CONTENT);
	}

	int childWidthSpec = ViewGroup.getChildMeasureSpec(0, 0 + 0, p.width);
	int lpHeight = p.height;
	int childHeightSpec;
	if (lpHeight > 0) {
	    childHeightSpec = MeasureSpec.makeMeasureSpec(lpHeight,
		    MeasureSpec.EXACTLY);
	} else {
	    childHeightSpec = MeasureSpec.makeMeasureSpec(0,
		    MeasureSpec.UNSPECIFIED);
	}
	child.measure(childWidthSpec, childHeightSpec);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent e) {
	int y = (int) e.getRawY();
	switch (e.getAction()) {
	case MotionEvent.ACTION_DOWN:
	    // 首先拦截down事件,记录y坐标
	    mLastMotionY = y;
	    break;
	case MotionEvent.ACTION_MOVE:
	    // deltaY > 0 是向下运动,< 0是向上运动
	    int deltaY = y - mLastMotionY;
	    if (isRefreshViewScroll(deltaY)) {
		return true;
	    }
	    break;
	case MotionEvent.ACTION_UP:
	case MotionEvent.ACTION_CANCEL:
	    break;
	}
	return false;
    }

    /*
     * 如果在onInterceptTouchEvent()方法中没有拦截(即onInterceptTouchEvent()方法中 return
     * false)则由PullToRefreshView 的子View来处理;否则由下面的方法来处理(即由PullToRefreshView自己来处理)
     */
    @Override
    public boolean onTouchEvent(MotionEvent event) {
	if (mLock) {
	    return true;
	}
	int y = (int) event.getRawY();
	switch (event.getAction()) {
	case MotionEvent.ACTION_DOWN:
	    // onInterceptTouchEvent已经记录
	    // mLastMotionY = y;
	    break;
	case MotionEvent.ACTION_MOVE:
	    int deltaY = y - mLastMotionY;
	    if (mPullState == PULL_DOWN_STATE) {
		// PullToRefreshView执行下拉
		// Log.i(TAG, " pull down!parent view move!");
		headerPrepareToRefresh(deltaY);
		// setHeaderPadding(-mHeaderViewHeight);
	    } else if (mPullState == PULL_UP_STATE) {
		// PullToRefreshView执行上拉
		// Log.i(TAG, "pull up!parent view move!");
		footerPrepareToRefresh(deltaY);
	    }
	    mLastMotionY = y;
	    break;
	case MotionEvent.ACTION_UP:
	case MotionEvent.ACTION_CANCEL:
	    int topMargin = getHeaderTopMargin();
	    if (mPullState == PULL_DOWN_STATE) {
		if (topMargin >= 0) {
		    // 开始刷新
		    headerRefreshing();
		} else {
		    // 还没有执行刷新，重新隐藏
		    setHeaderTopMargin(-mHeaderViewHeight);
		}
	    } else if (mPullState == PULL_UP_STATE) {
		if (Math.abs(topMargin) >= mHeaderViewHeight
			+ mFooterViewHeight) {
		    // 开始执行footer 刷新
		    footerRefreshing();
		} else {
		    // 还没有执行刷新，重新隐藏
		    setHeaderTopMargin(-mHeaderViewHeight);
		}
	    }
	    break;
	}
	return super.onTouchEvent(event);
    }

    /**
     * 是否应该到了父View,即PullToRefreshView滑动
     * 
     * @param deltaY
     *            , deltaY > 0 是向下运动,< 0是向上运动
     */
    private boolean isRefreshViewScroll(int deltaY) {
	if (mHeaderState == REFRESHING || mFooterState == REFRESHING) {
	    return false;
	}
	// 对于ListView和GridView
	if (mAdapterView != null) {
	    // 子view(ListView or GridView)滑动到最顶端
	    if (deltaY > 0) {

		View child = mAdapterView.getChildAt(0);
		if (child == null) {
		    // 如果mAdapterView中没有数据,不拦截
		    return false;
		}
		if (mAdapterView.getFirstVisiblePosition() == 0
			&& child.getTop() == 0) {
		    mPullState = PULL_DOWN_STATE;
		    return true;
		}
		int top = child.getTop();
		int padding = mAdapterView.getPaddingTop();
		if (mAdapterView.getFirstVisiblePosition() == 0
			&& Math.abs(top - padding) <= 8) {// 这里之前用3可以判断,但现在不行,还没找到原因
		    mPullState = PULL_DOWN_STATE;
		    return true;
		}

	    } else if (deltaY < 0) {
		View lastChild = mAdapterView.getChildAt(mAdapterView
			.getChildCount() - 1);
		if (lastChild == null) {
		    // 如果mAdapterView中没有数据,不拦截
		    return false;
		}
		// 最后一个子view的Bottom小于父View的高度说明mAdapterView的数据没有填满父view,
		// 等于父View的高度说明mAdapterView已经滑动到最后
		if (lastChild.getBottom() <= getHeight()
			&& mAdapterView.getLastVisiblePosition() == mAdapterView
				.getCount() - 1) {
		    mPullState = PULL_UP_STATE;
		    return true;
		}
	    }
	}
	// 对于ScrollView
	if (mScrollView != null) {
	    // 子scroll view滑动到最顶端
	    View child = mScrollView.getChildAt(0);
	    if (deltaY > 0 && mScrollView.getScrollY() == 0) {
		mPullState = PULL_DOWN_STATE;
		return true;
	    } else if (deltaY < 0
		    && child.getMeasuredHeight() <= getHeight()
			    + mScrollView.getScrollY()) {
		mPullState = PULL_UP_STATE;
		return true;
	    }
	}
	return false;
    }

    /**
     * header 准备刷新,手指移动过程,还没有释放
     * 
     * @param deltaY
     *            ,手指滑动的距离
     */
    private void headerPrepareToRefresh(int deltaY) {
	int newTopMargin = changingHeaderViewTopMargin(deltaY);
	// 当header view的topMargin>=0时，说明已经完全显示出来了,修改header view 的提示状态
	if (newTopMargin >= 0 && mHeaderState != RELEASE_TO_REFRESH) {
	    mHeaderTextView.setText(Config.changeLanguage(MyAppliction.mCn).getDownloading());
	    mHeaderUpdateTextView.setVisibility(View.VISIBLE);
	    mHeaderImageView.clearAnimation();
	    mHeaderImageView.startAnimation(mFlipAnimation);
	    mHeaderState = RELEASE_TO_REFRESH;
	} else if (newTopMargin < 0 && newTopMargin > -mHeaderViewHeight) {// 拖动时没有释放
	    mHeaderImageView.clearAnimation();
	    mHeaderImageView.startAnimation(mFlipAnimation);
	    // mHeaderImageView.
	    mHeaderTextView.setText(Config.changeLanguage(MyAppliction.mCn).getDown());
	    mHeaderState = PULL_TO_REFRESH;
	}
    }

    /**
     * footer 准备刷新,手指移动过程,还没有释放 移动footer view高度同样和移动header view
     * 高度是一样，都是通过修改header view的topmargin的值来达到
     * 
     * @param deltaY
     *            ,手指滑动的距离
     */
    private void footerPrepareToRefresh(int deltaY) {
	int newTopMargin = changingHeaderViewTopMargin(deltaY);
	// 如果header view topMargin 的绝对值大于或等于header + footer 的高度
	// 说明footer view 完全显示出来了，修改footer view 的提示状态
	if (Math.abs(newTopMargin) >= (mHeaderViewHeight + mFooterViewHeight)
		&& mFooterState != RELEASE_TO_REFRESH) {
	    mFooterTextView
		    .setText(Config.changeLanguage(MyAppliction.mCn).getUpdateloading());
	    mFooterImageView.clearAnimation();
	    mFooterImageView.startAnimation(mFlipAnimation);
	    mFooterState = RELEASE_TO_REFRESH;
	} else if (Math.abs(newTopMargin) < (mHeaderViewHeight + mFooterViewHeight)) {
	    mFooterImageView.clearAnimation();
	    mFooterImageView.startAnimation(mFlipAnimation);
	    mFooterTextView.setText(Config.changeLanguage(MyAppliction.mCn).getUpdate());
	    mFooterState = PULL_TO_REFRESH;
	}
    }

    /**
     * 修改Header view top margin的值
     * 
     * @description
     * @param deltaY
     */
    private int changingHeaderViewTopMargin(int deltaY) {
	LayoutParams params = (LayoutParams) mHeaderView.getLayoutParams();
	float newTopMargin = params.topMargin + deltaY * 0.3f;
	// 这里对上拉做一下限制,因为当前上拉后然后不释放手指直接下拉,会把下拉刷新给触发了,感谢网友yufengzungzhe的指出
	// 表示如果是在上拉后一段距离,然后直接下拉
	if (deltaY > 0 && mPullState == PULL_UP_STATE
		&& Math.abs(params.topMargin) <= mHeaderViewHeight) {
	    return params.topMargin;
	}
	// 同样地,对下拉做一下限制,避免出现跟上拉操作时一样的bug
	if (deltaY < 0 && mPullState == PULL_DOWN_STATE
		&& Math.abs(params.topMargin) >= mHeaderViewHeight) {
	    return params.topMargin;
	}
	params.topMargin = (int) newTopMargin;
	mHeaderView.setLayoutParams(params);
	invalidate();
	return params.topMargin;
    }

    /**
     * header refreshing
     */
    private void headerRefreshing() {
	mHeaderState = REFRESHING;
	setHeaderTopMargin(0);
	mHeaderImageView.setVisibility(View.GONE);
	mHeaderImageView.clearAnimation();
	mHeaderImageView.setImageDrawable(null);
	mHeaderProgressBar.setVisibility(View.VISIBLE);
	mHeaderTextView.setText(Config.changeLanguage(MyAppliction.mCn).getDownloading());
	if (mOnHeaderRefreshListener != null) {
	    mOnHeaderRefreshListener.onHeaderRefresh(this);
	}
    }

    /**
     * footer refreshing
     */
    private void footerRefreshing() {
	mFooterState = REFRESHING;
	int top = mHeaderViewHeight + mFooterViewHeight;
	setHeaderTopMargin(-top);
	mFooterImageView.setVisibility(View.GONE);
	mFooterImageView.clearAnimation();
	mFooterImageView.setImageDrawable(null);
	mFooterProgressBar.setVisibility(View.VISIBLE);
	mFooterTextView
		.setText(Config.changeLanguage(MyAppliction.mCn).getUpdateloading());
	if (mOnFooterRefreshListener != null) {
	    mOnFooterRefreshListener.onFooterRefresh(this);
	}
    }

    /**
     * 设置header view 的topMargin的值
     * 
     * @description
     * @param topMargin
     *            ，为0时，说明header view 刚好完全显示出来； 为-mHeaderViewHeight时，说明完全隐藏了
     */
    private void setHeaderTopMargin(int topMargin) {
	LayoutParams params = (LayoutParams) mHeaderView.getLayoutParams();
	params.topMargin = topMargin;
	mHeaderView.setLayoutParams(params);
	invalidate();
    }

    /**
     * header view 完成更新后恢复初始状态;即，重新隐藏添加的控件，只显示数据
     */
    public void onHeaderRefreshComplete() {
	setHeaderTopMargin(-mHeaderViewHeight);
	mHeaderImageView.setVisibility(View.VISIBLE);
	mHeaderImageView.setImageResource(R.drawable.ic_pulltorefresh_arrow);
	mHeaderTextView.setText(Config.changeLanguage(MyAppliction.mCn).getDown());
	mHeaderProgressBar.setVisibility(View.GONE);
	mHeaderUpdateTextView.setText(mLastUpdateTime);
	mHeaderState = PULL_TO_REFRESH;
    }

    /**
     * Resets the list to a normal state after a refresh.
     * 
     * @param lastUpdated
     *            Last updated at.
     */
    public void onHeaderRefreshComplete(CharSequence lastUpdated) {
	mLastUpdateTime = (String) lastUpdated;
	setLastUpdated(lastUpdated);
	onHeaderRefreshComplete();
    }

    /**
     * footer view 完成更新后恢复初始状态
     */
    public void onFooterRefreshComplete() {
	setHeaderTopMargin(-mHeaderViewHeight);
	mFooterImageView.setVisibility(View.VISIBLE);
	mFooterImageView.setImageResource(R.drawable.ic_pulltorefresh_arrow_up);
	mFooterTextView.setText(Config.changeLanguage(MyAppliction.mCn).getDownloading());
	mFooterProgressBar.setVisibility(View.GONE);
	 mHeaderUpdateTextView.setText(mLastUpdateTime);
	mFooterState = PULL_TO_REFRESH;
    }

    /**
     * Set a text to represent when the list was last updated.
     * 
     * @param lastUpdated
     *            Last updated at.
     */
    public void setLastUpdated(CharSequence lastUpdated) {
	if (lastUpdated != null) {
	    mHeaderUpdateTextView.setVisibility(View.VISIBLE);
	    mHeaderUpdateTextView.setText(lastUpdated);
	} else {
	    mHeaderUpdateTextView.setVisibility(View.GONE);
	}
    }

    /**
     * 获取当前header view 的topMargin
     * 
     * @description
     */
    private int getHeaderTopMargin() {
	LayoutParams params = (LayoutParams) mHeaderView.getLayoutParams();
	return params.topMargin;
    }

    /**
     * lock
     */
    private void lock() {
	mLock = true;
    }

    /**
     * unlock
     */
    private void unlock() {
	mLock = false;
    }

    /**
     * set headerRefreshListener
     * 
     * @description
     * @param headerRefreshListener
     */
    public void setOnHeaderRefreshListener(
	    OnHeaderRefreshListener headerRefreshListener) {
	mOnHeaderRefreshListener = headerRefreshListener;
    }

    public void setOnFooterRefreshListener(
	    OnFooterRefreshListener footerRefreshListener) {
	mOnFooterRefreshListener = footerRefreshListener;
    }

    /**
     * Interface definition for a callback to be invoked when list/grid footer
     * view should be refreshed.
     */
    public interface OnFooterRefreshListener {
	public void onFooterRefresh(PullToRefreshView view);
    }

    /**
     * Interface definition for a callback to be invoked when list/grid header
     * view should be refreshed.
     */
    public interface OnHeaderRefreshListener {
	public void onHeaderRefresh(PullToRefreshView view);
    }
}
